Intrauterine position effects in male and female swine: subsequent survivability, growth rate, morphology and semen characteristics     

K A Rohde Parfet  W R Lamberson  A R Rieke  T C Cantley  V K Ganjam  F S vom Saal  B N Day 《Journal of animal science》1990,68(1):179-185

Pigs of known intrauterine position were obtained from 31 litters by a procedure in which donor sows were slaughtered at d 112 of gestation, their uteri removed and piglets delivered manually. Uterine position was recorded for each piglet as being positioned between two female fetuses (OM), between a male and female fetus (1M), between two male fetuses (2M), between a female fetus and the tip of the uterine horn (OE) or between a male fetus and the tip of the horn (1E). Piglets were fostered as litter groups to recipient sows and reared in these groups until 120 d of age. They then were regrouped and housed as groups of three and six for males and females, respectively. Intrauterine position had no effect on birth weight or survivability of pigs of either sex, although pigs positioned in utero nearest the ovaries (OE and 1E) tended to be heavier at birth. Body weights were similar among groups in each sex at 120 and 175 d of age when given ad libitum access to feed; however, 2M males gained more weight from d 175 to 270 under restricted feeding conditions (P less than .05). Intrauterine position had no effect on anogenital distances either at birth or 120 d of age, and predicted testes weights were similar among males from different positions. Semen characteristics at 220 d of age did not appear to vary due to prenatal environment. Although volume tended to be less for 0M males (P less than .12), concentration, motility and sperm/ejaculate were similar among groups.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

Seasonal and pulsatile dynamics of thyrotropin and leptin in mares maintained under a constant energy balance     

Buff PR  Messer NT  Cogswell AM  Johnson PJ  Keisler DH  Ganjam VK 《Domestic animal endocrinology》2007,33(4):430-436

The objective of this study was to determine if seasonal and/or pulsatile variations occur in plasma concentrations of thyrotropin (TSH) and leptin in mares while maintaining a constant energy balance. Blood samples were collected every 20 min during a 24 h period in winter and again in summer from six Quarter Horse type mares. Plasma concentrations of TSH, leptin, and T₄ were determined by radioimmunoassay. No differences were observed in body weight between winter (388.1 ± 12.5 kg) and summer (406.2 ± 12.5 kg; P = 0.11). Plasma concentrations of TSH were greater in the summer (2.80 ± 0.07 ng/ml) when compared to winter (0.97 ± 0.07 ng/ml; P < 0.001). Pulse frequency of TSH was not different between winter (6.17 ± 0.78 pulses/24 h) and summer (5.33 ± 0.78 pulses/24 h; P = 0.49). Mean TSH pulse amplitude, pulse area, and area under the curve were all greater in summer compared to winter (3.11 ± 0.10 ng/ml versus 1.20 ± 0.10 ng/ml, 24.86 ± 0.10 ng/ml min versus 13.46 ± 1.90 ng/ml min, 3936 ± 72.93 ng/ml versus 1284 ± 72.93 ng/ml, respectively; P < 0.01). Mean concentrations of leptin were greater in summer (2.48 ± 0.17 ng/ml) compared to winter (0.65 ± 0.17 ng/ml; P < 0.001). Pulsatile secretion patterns of leptin were not observed in any horses during experimentation. Mean concentrations of T₄ were greater in winter (20.3 ± 0.4 ng/ml) compared to summer (18.2 ± 0.4 ng/ml; P < 0.001). These seasonal differences between winter and summer provide evidence of possible seasonal regulation of TSH and leptin.  相似文献   

Expression of endothelin in equine laminitis.     

L C Katwa  P J Johnson  V K Ganjam  J M Kreeger  N T Messer 《Equine veterinary journal》1999,31(3):243-247

Biosynthesis of endothelin-1 (ET-1), the most potent endogenous vasoconstrictor yet identified, is increased following myocardial infarction (MI) in man. Pathological events which occur in the connective tissues of the equine hoof during laminitis are similar in some respects, to changes occurring in the myocardial connective tissues following MI in man. The objective of this study was to determine whether ET-1 expression in connective tissues obtained from the hoof of laminitic horses is increased compared with tissues obtained from healthy horses. Expression of ET-1 in connective tissues of the equine hoof was measured following tissue extraction from 3 groups of horses: horses in which acute laminitis had been induced by the administration of starch; chronically foundered horses; nonlaminitic horses. The concentration of ET-1 in laminar connective tissues obtained from all laminitic horses (1573.0 +/- 392.8 pg/g of tissue; n = 10) was increased when compared with tissues obtained from nonlaminitic horses (392.5 +/- 117.4 pg/g of tissue; n = 5) (P<0.05). The concentration of ET-1 in laminar connective tissues obtained from the experimentally induced, acute laminitic horses (1043.6 +/- 254.4 pg/g of tissue; n = 7) and from the spontaneously affected, chronic laminitic horses (2808.3 +/- 878.6 pg/g of tissue; n = 3) was increased compared with the control group (P<0.05, P<0.01, respectively). The concentration of ET-1 in laminar connective tissues obtained from the chronic laminitic horses was greater than that of the experimentally induced, acute laminitic group (P<0.05). It is suggested that the data provide a strong argument that increased ET-1 expression in the connective tissues of the equine hoof represent a potentially important and hitherto unrecognised component of the pathophysiology of equine laminitis. Further studies are needed to determine whether inhibitors of ET-1 converting enzyme or antagonists of ET-1 receptors might be useful in the treatment and prevention of laminitis in horses.  相似文献